This invention relates to a process for preparing cured meat and, more particularly, to a process for preparing cured meat which, when cooked, will have reduced levels of N-nitrosamines.
For many years it has been common practice to prepare cured meat by treating the uncured meat with a curing composition and then smoking the cured product to impart a desirable flavor. A major component of the composition is sodium nitrite which inhibits the germination of Clostridium botulinum spores, thus ensuring that the cured product will be free of the deadly toxin produced by this bacterium. In recent years, however, much controversy has surrounded the use of sodium nitrite because there have been allegations that residual nitrite from the curing composition can react with organic amines present in various cured meat products to form carcinogenic nitrosamines. This problem is accentuated with certain products because nitrosamine formation is induced by the elevated temperatures encountered when these products are cooked for consumption; i.e., those exceeding 300.degree. F.
Many approaches have been considered in seeking a remedy to this problem and proposed remedies have included eliminating nitrite from the curing composition or reducing residual nitrite levels in the cured product. Neither of these approaches is particularly satisfactory, however, because there is presently no suitable substitute for nitrite, and because reducing nitrite levels could increase the likelihood that C. botulinum spores would grow in the cured product.
Another approach has involved a search for substances to be added to the curing composition which might inhibit the formation of nitrosamines by interfering in some way with the nitrite/amine reaction by which the nitrosamines are formed. This approach has been hampered by the unpredictability of chemical reactions in the complex meat system which forms the environment for the reaction in question. Although results obtained by various workers have, for this reason, been inconsistent and contradictory, a number of substances have been identified which appear to exhibit some degree of inhibitory effect. For example, compounds such as sodium ascorbate, sodium erythorbate, alpha-tocopherol, etc. have been reported in the literature as having the ability to reduce nitrosamine formation. (See Fiddler et al, J. Agric. Food Chem., Vol. 26, No. 3, 1978.)
One of the deficiencies of the inhibiting substances referred to above is their limited inhibitory action. In most cases, the substances have been found to cause nitrosamine reductions of up to 50%, but this still leaves a substantial problem in dealing with the remaining 50%. There has been an intensive search for more potent means of inhibiting the nitrosamine reaction.
My co-pending application Ser. No. 286,743, supra, describes an invention which is based on the discovery that substantially greater nitrosamine reductions can be achieved in cured meats by introducing into the uncured meat a nitrite curing composition, together with a tocopherol and an additional inhibiting substance which may be either a liquid smoke or a reducing sugar, or a combination thereof, and thereafter processing the meat to effect curing. In the making of said invention it was found that, while the tocopherol, the liquid smoke and the reducing sugar each is capable of reducing nitrosamines, the above combinations provide reductions substantially greater than can be obtained with any of the inhibitors used alone. Moreover, it was found that the improved inhibitory action could be obtained without significantly affecting the level of residual nitrite in the cured meat and thus the combination of inhibitors while reducing nitrosamine levels does not interfere with the C. botulinum protection offered by the nitrite itself.